The present invention relates generally to the field of magnetic storage devices such as magnetic tape drives and hard disk drives, and more particularly to configuring operational parameters for reader elements incorporated into magnetic storage devices.
Tunneling magnetoresistive (“TMR”) sensors are microelectronic devices that are characterized by a change in electrical resistance in response to changes of a magnetic field. In recent years, new magnetic storage devices, such as magnetic tape drives and hard disk drives, have been developed that rely upon TMR sensors to read data from magnetic media. Different regions of magnetic media correspond to bits of data, each of which can apply either of two different magnetic field states to the TMR sensor. The value of each bit, one or zero, can be determined electronically by measuring resistance across the TMR sensor such that one state may be characterized by a relatively high resistance and the other characterized by a relatively low resistance.
As with all microelectronic devices, TMR sensors experience hardware failures of various kinds. In particular, TMR sensors can experience dielectric breakdown with a risk factor that generally increases over the product lifetime. Since a magnetic storage product may include multiple read head devices, each incorporating multiple TMR-based reader elements, Engineers and designers of product firmware face challenges in quantifying the risk of any individual TMR-based reader element experiencing dielectric breakdown.